[Obstructive sleep apnea hypopnea syndrome and alveolar hypoventilation syndrome in motor neuron disease: A case report and literature review].

To investigate the clinical characteristics of a patient with motor neuron disease, which caused sleep-disordered breathing (SDB) and alveolar hypoventilation syndrome, and to improve the diagnosis rate for this disease.
 Methods: Retrospectively analyze the diagnosis and treatment process for a 52 year-old male patient, who was accepted by the Second Xiangya Hospital, Central South University because of dyspnea, shortness of breath and malaise for 4 months, and eventually was diagnosed as motor neuron disease associated with obstructive sleep apnea hypopnea syndrome and alveolar hypoventilation syndrome. In addition, we searched CNKI, Wanfang and PubMed databases to review relevant literature with keywords (motor neuron disease or amyotrophic lateral sclerosis or progressive bulbar palsy or progressive muscular atrophy or primary lateral sclerosis) AND (sleep apnea or sleep disordered breathing) from January 1990 to May 2017.
 Results: The major clinical manifestation of motor neuron disease included impaired upper and lower motor neuron displayed with proximal muscle weakness, muscle tremor, amyotrophy, bulbar symptoms and pyramidal sign. It was a chronic, progressive disease with worse prognosis, low survival and difficult in diagnosis. Electroneuromyography was a vital way for diagnosis. Furthermore, sleep disordered breathing was common in patients with motor neuron disease, which was featured as decreased rapid eye movement sleep, increased awaking time, apnea and hypopnea. The main mechanism for sleep disordered breathing in motor neuron disease might be due to the disturbed central nervous system and paralysis of diaphragm and respiratory muscle. Moreover, the patient suffered from restrictive ventilatory dysfunction, alveolar hypoventilation and subsequent partial pressure of carbon dioxide and hypoxemia. Therefore, respiratory failure was the most frequent cause of death for patients with motor neuron disease. Non-invasive positive pressure ventilation was suggested to apply to such patients, whose forced vital capability was less than 75 percent of predicted value.
 Conclusion: Sleep disordered breathing is common in patients with motor neuron disease. Hence, polysomnography is suggested as a routine examination to confirm the potential complications and give timely therapy. Treatment with non-invasive positive pressure ventilation is important for patients to improve life quality, survival rate and prognosis.